Fishline cutter for marine propulsion units

ABSTRACT

A cutter is mounted on the inner end of the propeller hub of an outboard marine propulsion unit to cut fishlines which become entangled upon the propeller and protect the gearcase seal from damage by the line.

United States Patent FISHLINE CUTTER FOR MARINE PROPULSION Relerences Cited UNITED STATES PATENTS Primary Examiner-Everette A. Powell, Jr.

UNITS 2 Claims 3 Drawing Figs. Attorney-Roy T. Montgomery US. Cl 416/93, 416/146 Int. Cl B63h 1/20 Field of Search ..4l6/l46, 93 fishlines which become entan M; 415/121 tect the gearcase seal from damage by the line.

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416/146 416/146 416/146 4l6/93M 416/93M 4l6/93M 416/146 ABSTRACT: A cutter is mounted on the inner end of the propeller hub of an outboard marine propulsion unit to cut gled upon the propeller and pro- PATENTEnunv 9 ran 3. 6 19.0 8 3 Attorneys FISHLINE CU'I'I'ER FOR MARINE PROPULSION UNITS BACKGROUND This invention relates to a fishline cutter on a marine propulsion unit to protect the gearcase seal from damage from a fishline becoming entangled upon the propeller.

The invention is believed to have no prior counterpart.

SUMMARY The fishline cutter generally comprises a simple stainless steel washer which may be clamped between the inner end of the propeller hub sleeve and a thrust collar on the shaft, and which washer has radially extending sharp knife edge teeth adapted to cut any fishline which starts to wind onto the shaft after being entangled with the propeller.

l-leretofore such fishlines have wound themselves upon the propeller shaft and into engagement with the seal between the bearing and the propeller, often damaging the seal and letting the oil in the gearcase escape.

The invention avoids this damage and effectively cuts even the very strong monofilament fishlines being used today.

DRAWING The invention is illustrated in the accompanying drawing in which:

FIG. 1 is a side elevation of a marine propulsion unit with parts broken away and sectioned to show the fishline cutter of the present invention incorporated therein;

FIG. 2 is an enlarged detail of the underwater portion partially sectioned to show the fishline cutter and thrust collar; and

FIG. 3 is a rear end elevation of the fishline cutter and thrust collar of FIG. 2.

BRIEF DESCRIPTION The marine propulsion unit illustrated is the lower unit of a small outboard motor customarily employed by fishermen. It comprises the usual streamlined underwater housing 1 having a gearcase torpedo-shaped portion 2 with the strut 3 above the same and connecting to the lower end of a drive shaft housing 4, and a skeg 5 depending beneath the gearcase 2.

A drive shaft 6 extends downwardly through the drive shaft housing 4 and strut 3 into the gearcase 2. An engine, not shown, is normally connected to the upper end of the drive shaft 6 to drive the same.

A horizontal propeller shaft 7 is mounted in suitable bearings axially of the gearcase 2 and is driven by suitable forward and reverse gears from the drive shaft 6. The gears and bearings in gearcase 2 are normally run in a suitable lubricant filling the gearcase.

The propeller shaft 7 extends rearwardly from the gearcase 2 and carries a propeller 8 thereon submerged in the water and which propels the boat to which the unit is attached.

The rear end of the gearcase 2 is closed by a spoollike member 9 which has passages 10 therein for conducting engine exhaust gases from housing 1 into the hub 11 of propeller 8.

The propeller hub 11 is hollow and is connected by generally radial struts 12 to an inner hub sleeve 13 mounted by a resilient member 14 on shaft 7. The hub has the customary propeller blades 15 cast integrally therewith.

The inner hub sleeve 13 normally bears against a thrust col lar l6 splined to shaft 7 at the forward end of the propeller.

The spoollike member 9 carries a seal 17 surrounding shaft 7 and which prevents leakage of lubricant from the gearcase 2. It is this seal that the present invention is intended to protect.

In carrying out the invention a simple stainless steel washer 18 is mounted within the hub 11 and between the thrust collar 16 and the adjacent end of the inner hub sleeve 13, and has a plurality of generally radial angularly disposed sharp cutter teeth 19 thereon.

The cutter teeth 19 engage and cut any fishline that tries to wind itself upon the rotating shaft adjacent seal l7, after which the remainder of the fishline is freed from the propeller, thus preventing possible damage to the seal 17.

The invention is claimed as follows:

I. The combination in a marine propulsion device having an underwater gearcase with a generally horizontal propeller shaft extending rearwardly therefrom and sealed therewith to retain lubricant in the gearcase, said shaft carrying a propeller and a propeller hub submerged in the water rearwardly of said seal, of a fishline cutter mounted within the hub and between the propeller and said seal to rotate with said shaft and preventing winding of entangled fishline upon the shaft adjacent said seal, said cutter comprising a thrust collar secured upon the shaft and carrying outwardly extending teeth and said propeller having a forward end bearing against said thrust collar.

2. The construction of claim 1, in which said propeller is resiliently mounted upon the shaft and said fishline cutter comprises a washer carried by said thrust collar and having outwardly extending teeth thereon adapted to cut a fishline winding thereon. 

1. The combination in a marine propulsion device having an underwater gearcase with a generally horizontal propeller shaft extending rearwardly therefrom and sealed therewith to retain lubricant in the gearcase, said shaft carrying a propeller and a propeller hub submerged in the water rearwardly of said seal, of a fishline cutter mounted within the hub and between the propeller and said seal to rotate with said shaft and preventing winding of entangled fishline upon the shaft adjacent said seal, said cutter comprising a thrust collar secured upon the shaft and carrying outwardly extending teeth and said propeller having a forward end bearing against said thrust collar.
 2. The construction of claim 1, in which said propeller is resiliently mounted upon the shaft and said fishline cutter comprises a washer carried by said thrust collar and having outwardly extending teeth thereon adapted to cut a fishline winding thereon. 